CN113425428A

CN113425428A - Method and system for constructing retention accessory and bracket-free invisible orthodontic appliance

Info

Publication number: CN113425428A
Application number: CN202110705580.4A
Authority: CN
Inventors: 郑轶刊; 侯俊祥
Original assignee: Wuxi Ea Medical Instruments Technologies Ltd
Current assignee: Wuxi Ea Medical Instruments Technologies Ltd
Priority date: 2021-06-24
Filing date: 2021-06-24
Publication date: 2021-09-24
Anticipated expiration: 2041-06-24
Also published as: CN113425428B

Abstract

The invention discloses a method and a system for constructing a retention accessory and a bracket-free invisible orthodontic appliance. The construction method comprises the following steps of obtaining a dentition model and a shell-shaped appliance model matched with the dentition model; selecting a mounting point in an accessory mounting selectable area on the dentition model, and constructing a retention accessory based on the mounting point, wherein the retention accessory comprises the following steps: taking off the shell-shaped appliance model worn on the dentition model from the dentition model, and acquiring the movement track of a reference point on the shell-shaped appliance model corresponding to the mounting point; establishing a tangent line of one key position point in the motion trail, or establishing a direct connection line of two key position points in the motion trail, and establishing the retention accessory according to a preset rule based on the tangent line or the direct connection line. Therefore, the retention force of the accessory to the appliance is improved, and the appliance is prevented from falling off accidentally.

Description

Method and system for constructing retention accessory and bracket-free invisible orthodontic appliance

Technical Field

The invention relates to a construction method and a construction system of a retention accessory, a computer readable storage medium and a bracket-free invisible orthodontic appliance, belonging to the technical field of orthodontic.

Background

The bracket-free invisible orthodontic device has the advantages of convenience in taking and wearing, comfort, attractive appearance, easiness in clinical use, convenience in oral hygiene cleaning and the like, so that the bracket-free invisible orthodontic technology is more and more popular. With the widespread use of the bracket-free invisible appliance, some disadvantages are gradually exposed to a plurality of patients with different oral conditions.

Wherein, the maintenance of ware is rescued in stealthy nothing support groove, except that the frictional force between ware and the tooth is rescued in the dependence, mainly still can rely on the annex of bonding on the tooth, nevertheless discover in the stealthy ware of rescuring in a large number of uses of no support groove, current annex can't produce sufficient retention force to the stealthy ware of rescuring in the support groove of no support groove, cause the stealthy ware of rescuring in the support groove to drop at the in-process accident of wearing.

In addition, for the accessory on the labial and buccal sides of the teeth, the bracket-free invisible appliance is further reduced by the retention action of the accessory due to the actions of the tongue licking and pressing and the like of the patient carelessly, so that the bracket-free invisible appliance can continuously fall off in the wearing process, and the orthodontic treatment cannot be continued.

Disclosure of Invention

The invention aims to provide a construction method and a construction system of a retention accessory, a computer readable storage medium and a bracket-free invisible appliance, wherein the accessory can ensure the retention force of the appliance, and the problem that the appliance is easy to fall off due to insufficient retention force of the accessory to the appliance in the prior art is solved.

To achieve the above object, one embodiment provides a method of constructing a retention attachment including a bottom surface for attachment to teeth, and a gingival side retention surface, a corner retention surface, and a distal side retention surface connected in sequence along a partial edge of the bottom surface, the method including the steps of,

acquiring a dentition model and a shell-shaped appliance model matched with the dentition model;

selecting a mounting point in an accessory mounting selectable area on the dentition model, and constructing a retention accessory based on the mounting point, wherein the retention accessory comprises the following steps:

taking off the shell-shaped appliance model worn on the dentition model from the dentition model, and acquiring the movement track of a reference point on the shell-shaped appliance model corresponding to the mounting point;

establishing a tangent line of one key position point or a direct connection line of two key position points in the motion trail, and constructing a retention accessory meeting the following rules:

rule one, the bottom surface is attached and matched with the accessory installation selectable area;

a second rule is that the intersection line of the gum side retention surface and the bottom surface is a first straight line, the intersection line of the gum side retention surface and the bottom surface has a highest point in the normal direction of the bottom surface, and a plane defined by the first straight line and the highest point forms an included angle of 60-90 degrees with the tangent line or the straight connecting line; or the intersection line of the gum side retention surface and the corner retention surface is a second straight line, the intersection line of the gum side retention surface and the bottom surface has a farthest point far away from the corner retention surface, and a plane defined by the second straight line and the farthest point forms an included angle of 60-90 degrees with the tangent line or the straight connecting line.

Further, the step of selecting a mounting point in the optional accessory mounting area on the dentition model and constructing the retention accessory based on the mounting point further comprises:

taking the tangent line or the straight connecting line in the step of establishing the tangent line of one key position point or the straight connecting line of two key position points in the motion trail as a first auxiliary line, and further establishing a second auxiliary line different from the first auxiliary line, wherein the second auxiliary line is the tangent line of one key position point or the straight connecting line of two key position points in the motion trail;

the retention accessory also satisfies rule four: two end points of an intersection line of the corner fixing surface and the bottom surface and a plane defined by the highest point form an included angle of 60-90 degrees with the second auxiliary line.

Further, the corner fixing surface is in a convex arc shape on a cross section perpendicular to the normal direction of the bottom surface.

Further, the key location point is selected from a start location point, an end location point defined by an intersection of a boundary of a normal projection space of the accessory mounting selectable region and the motion trajectory, and a transition location point between the start location point and the end location point.

Further, the first auxiliary line is set as a tangent line of the starting position point, and the second auxiliary line is set as a straight connecting line of the starting position point and the ending position point.

Further, any one of the gingival side retention surface, the corner retention surface, and the distal side retention surface is set to: and extends away from the bottom surface along a straight line at an included angle of 60-120 degrees with the bottom surface.

Further, the gum side retention surface and the far side retention surface are respectively set to be a plane or a curved surface, and the corner retention surface is set to be a cylindrical arc surface.

Further, the intersection line of the gum side retention surface and the bottom surface has a farthest point far away from the corner retention surface and a nearest point intersecting with the corner retention surface;

the intersection line of the far middle side retaining surface and the bottom surface is provided with a far point far away from the corner retaining surface and a near point intersecting with the corner retaining surface;

the step of establishing a tangent line of one key position point or a direct connection line of two key position points in the motion trail and establishing the retention accessory meeting the following rules also has a rule three: on a projection plane along the normal direction of the bottom surface, a straight connecting line from the closest point to the farthest point forms an included angle of 60-120 degrees with a straight connecting line from the extremely close point to the extremely far point.

Further, the gingival side retention surface is configured to: the plane is formed by two end points of the intersecting line of the bottom surface and the highest point and forms an included angle of 60-120 degrees with the bottom surface;

and/or the corner retention surface is configured to: the plane is formed by the extremely close point, the closest point and the highest point and forms an included angle of 60-120 degrees with the bottom surface;

and/or the distal retention surface is configured to: the plane is formed by two end points of the intersection line of the bottom surface and the highest end point of the intersection line of the corner fixing surface in the normal direction of the bottom surface, and forms an included angle of 60-120 degrees with the bottom surface.

Furthermore, on a projection plane along the normal direction of the bottom surface, a straight connecting line of the farthest point and the nearest point forms an included angle of 60-90 degrees with a tooth major axis of a tooth where the accessory installation selectable region is located;

and/or on a projection plane along the normal direction of the bottom surface, a direct connection line of the extreme far point and the extreme near point forms an included angle of 0-45 degrees with a tooth major axis of a tooth in which the accessory installation selectable region is positioned.

Further, an upper edge of any one of the gingival side retention surface, the corner retention surface, and the distal side retention surface defines a maximum height of the retention attachment in a normal direction of the floor surface.

Further, in the step of "obtaining a movement locus of a reference point corresponding to the mounting point on the shell-shaped appliance model": sequentially recording N coordinates of the reference point in a space coordinate system, and fitting the N coordinates into a curve in sequence, wherein the curve forms the motion track; n is more than or equal to 2, and the N coordinates comprise the initial coordinates of the reference points when the shell-shaped appliance model is worn on the dentition model.

Further, the attachment mounting selectable area is located on a labial and buccal surface of the dentition model;

the step of taking off the shell-shaped appliance model worn on the dentition model from the dentition model comprises the following steps: taking the lingual side of the shell-shaped appliance model as an action area of an actuating force, and taking off the shell-shaped appliance model worn on the dentition model from the dentition model by adopting the actuating force;

wherein the actuation force is directed along the long axis of the tooth toward the bite end; alternatively, the actuation force has a component directed along the long axis of the tooth toward the occlusal end and a component directed perpendicular to the long axis of the tooth toward the labial and buccal surfaces.

Further, the step of detaching the shell-shaped appliance model worn on the dentition model from the dentition model comprises: and taking the midpoint of the gingival edge of the lingual side of the final molar shell unit of the shell-shaped appliance model as the action area of the actuating force.

Further, the accessory installation selectable region has two or more installation points to be selected, in the construction method, all the installation points are traversed to sequentially execute for each installation point: the step of selecting a mounting point in the accessory mounting selectable area on the dentition model and constructing the retention accessory based on the mounting point; evaluating the retention force of the constructed retention accessory;

the construction method further comprises the steps of: and determining the final retention accessories and the corresponding mounting points thereof according to the optimal principle of the maximum retention force in all the constructed retention accessories.

Furthermore, a plurality of nodes distributed in a row-column matrix manner are planned in the accessory installation selectable area, and all or part of the nodes are used as installation points to be selected.

Further, the "two or more mounting points to be selected" may include two or more of an inner center point, a mesial edge occlusal end point, a mesial edge gum end point, a distal edge center point, a distal edge occlusal end point, a distal edge gum end point, an occlusal edge center point, and a gum edge center point of the accessory mounting selectable region.

Further, the step of "evaluating the retention force of the constructed retention fitting" includes:

adding the constructed retention accessories on the dentition model to serve as a second dentition model, and obtaining a second shell-shaped appliance model matched with the second dentition model;

and acquiring an actuating force for taking off the second shell-shaped appliance model worn on the second dentition model from the second dentition model, wherein the actuating force is used as a retaining force of the retaining accessory.

In order to achieve the above object, one embodiment provides a system for constructing a retention accessory, including a memory and a processor, the memory storing a computer program executable on the processor, the processor implementing the steps of the construction method when executing the computer program.

To achieve the above object, one embodiment provides a computer-readable storage medium on which a computer program is stored, the computer program implementing the steps in the construction method when executed by a processor.

In order to achieve the above object, one embodiment of the present invention provides a bracket-free invisible orthosis, including:

the shell-shaped appliance encloses an inner cavity capable of containing dentition and is provided with an accessory containing groove communicated with the inner cavity; and the number of the first and second groups,

the retaining accessory is constructed by the construction method, the bottom surface of the retaining accessory is used for being attached to teeth on the dentition, and the gum side retaining surface, the corner retaining surface and the far and middle side retaining surface are all abutted against the groove surface of the accessory accommodating groove so as to prevent the appliance from being separated from the dentition.

Further, the orthosis includes a buccal labial shell and a lingual shell, and the attachment receiving groove is provided in the buccal labial shell and is located at any one or more of shell units of the orthosis corresponding to molars and premolars.

Further, the attachment receiving slot is located in a shell unit of the appliance corresponding to a last molar and/or in a shell unit of the appliance corresponding to a last second tooth.

Compared with the prior art, the invention has the beneficial effects that: through the design optimization of the retention accessories, the retention force of the retention accessories to the appliance can be improved, and the problem that the appliance is easy to fall off due to the insufficient retention force of the retention accessories to the appliance in the prior art is solved.

Drawings

FIG. 1 is a flow chart of a method of constructing a retention attachment according to embodiment 1 of the present invention;

FIG. 2 is a schematic view of a dentition model and a shell appliance model according to example 1 of the present invention;

FIG. 3 is a schematic view of a shell-shaped appliance model of example 1 of the present invention worn on a dentition model;

FIG. 4 is a schematic view of a shell-shaped appliance model of example 1 of the present invention removed from a dentition model;

FIG. 5 is a schematic diagram of the movement locus of a reference point in a space coordinate system according to embodiment 1 of the present invention;

FIG. 6 is a schematic structural view of a bracket-less invisible orthodontic appliance of embodiment 1 of the invention, illustrating a state in which the retention attachment is mounted on a tooth;

FIGS. 7a to 7c are schematic views of the retention attachment according to embodiment 1 of the present invention, wherein FIG. 7a is a schematic view showing a perspective structure of the retention attachment, FIG. 7b is a schematic view showing a projection of the retention attachment along a normal direction of a bottom surface thereof, and FIG. 7c is a schematic view showing a cross section taken along a line A-A of FIG. 7a, the cross section being parallel to a normal line of the bottom surface and passing through a maximum height point of the retention attachment in the normal direction of the bottom surface;

FIGS. 7d and 7e are schematic views showing a projection of the retention aid in a simple modification of embodiment 1 of the present invention, taken along a direction normal to the bottom surface thereof;

FIG. 8a is a view of the structure of a tooth fitted with the retention fitting of example 1 of the present invention on the labial and buccal surfaces;

fig. 8b is a structural view of the housing unit with the accommodating groove on the labial and buccal sides according to embodiment 1 of the present invention;

FIGS. 9a to 9c are schematic views of the retention fitting according to embodiment 2 of the present invention, wherein FIG. 9a is a schematic view showing a perspective structure of the retention fitting, FIG. 9b is a schematic view showing a projection of the retention fitting along a normal direction of a bottom surface thereof, and FIG. 9c is a schematic view showing a cross section taken along a line A-A of FIG. 9a, the cross section being parallel to a normal line of the bottom surface and passing through a maximum height point of the retention fitting in the normal direction of the bottom surface;

FIGS. 10a to 10b are schematic views of the retention attachment according to embodiment 3 of the present invention, wherein FIG. 10a is a schematic view showing a perspective structure of the retention attachment, and FIG. 10b is a schematic view showing a projection of the retention attachment in a direction normal to a bottom surface thereof;

FIGS. 11a to 11b are schematic views of the retention attachment according to embodiment 4 of the present invention, wherein FIG. 11a is a schematic view showing a perspective structure of the retention attachment, and FIG. 11b is a schematic view showing a projection of the retention attachment in a direction normal to a bottom surface thereof;

12 a-12 b are schematic views of the retention fitting of embodiment 5 of the present invention, wherein FIG. 12a is a schematic view of a perspective structure of the retention fitting, and FIG. 12b is a schematic view of a projection of the retention fitting along a normal direction of a bottom surface thereof;

FIGS. 13 a-13 b are schematic views of the retention fitting of embodiment 6 of the present invention, wherein FIG. 13a is a schematic view of a perspective structure of the retention fitting, and FIG. 13b is a schematic view of a projection of the retention fitting along a normal direction of a bottom surface thereof;

fig. 14a to 14c are schematic views of the retention fitting according to embodiment 7 of the present invention, wherein fig. 14a is a schematic view of a three-dimensional structure of the retention fitting, fig. 14b is a schematic view of a projection of the retention fitting along a normal direction of a bottom surface thereof, and fig. 14c is a schematic view of a cross section along a line a-a of fig. 14a, the cross section being parallel to a normal line of the bottom surface and passing through a maximum height point of the retention fitting in the normal direction of the bottom surface;

FIG. 15 is a flow chart of a method of constructing a retention attachment according to embodiment 8 of the present invention;

fig. 16 is a schematic view of an accessory mounting optional area of embodiment 8 of the present invention.

Detailed Description

The embodiments of the present invention will be described in detail below with reference to specific examples shown in the drawings. These examples are not intended to limit the present invention, and structural, methodological, or functional changes made by those skilled in the art according to these embodiments are included in the scope of the present invention.

Example 1

Referring to fig. 1 to 8b, a method for constructing a retention accessory in a bracket-free invisible orthodontic appliance is disclosed in the present embodiment, and the method is used for constructing the retention accessory in a design stage, particularly constructing a retention surface 12 and a bottom surface of the retention accessory; in addition, the embodiment also discloses the retention accessory 10 constructed by adopting the construction method, and further discloses a bracket-free invisible orthodontic appliance adopting the retention accessory 10.

Referring to fig. 1, the construction method includes the following steps.

Step S101, obtaining a dentition model and a shell-shaped appliance model matched with the dentition model.

This step, in conjunction with FIG. 2, for example, obtains a dentition model 100 and a shell appliance model 200.

Wherein, the dentition model 100 may be either one of a maxillary dentition model and a mandibular dentition model, or a combination of the maxillary dentition model and the mandibular dentition model; in addition, the dentition model 100 may correspond to a complete dentition as shown in fig. 2, and may be variously implemented to correspond to a portion of a complete dentition, for example, a portion of the dentition remaining after incisors are removed on the basis of the complete dentition as shown in fig. 2, which is, of course, only an example for easy understanding.

Conventionally, in orthodontic procedures, the dentition layout has a series of intermediate layout states from an initial layout state to a final layout state. In this step, the dentition layout of the dentition model 100 may be a starting layout state or any intermediate layout state, but is not limited thereto.

Furthermore, as is known, in the orthodontic process of teeth, the shell-shaped appliance is worn on the dentition and is in an elastic deformation state, and the natural form (i.e. the inelastic deformation state) of the shell-shaped appliance is consistent with the next dentition layout state of the current dentition layout, so that the current dentition layout is gradually corrected to the next dentition layout state under the driving of the shell-shaped appliance, and the orthodontic treatment at this stage is completed.

In this step S101, as shown in fig. 2, the shell-shaped appliance model 200 is matched to the dentition model 100, that is, it can be worn on the dentition model 100, and its theoretical natural form coincides with the next dentition layout state of the dentition model 100 in the orthodontic plan, for example: when the dentition layout of the dentition model 100 is the initial layout state of the orthodontic process, the matched shell-shaped appliance model 200 is a model of a shell-shaped appliance for correcting the dentition from the initial layout state to a first intermediate layout state according to the orthodontic plan; when the dentition layout of the dentition model 100 is the last intermediate layout state in the orthodontic process, the shell-shaped appliance model 200 matched with the dentition model is a shell-shaped appliance model for correcting the dentition from the last intermediate layout state to the final layout state according to the orthodontic plan; by analogy, enumeration is not performed.

Further, in step S101, the dentition model 100 and the shell appliance model 200 may be implemented as a digital model or a solid model, respectively.

For example, for dentition model 100: in one embodiment, a scanning device is used to scan the oral cavity or the plaster model obtained by casting after traditional model taking to obtain dentition data, and based on the dentition data, a digital dentition model can be obtained by combining the dentition layout states of each stage in the orthodontic plan, so that the step S101 is implemented by obtaining the digital dentition model; in another embodiment, after the digital dentition model is obtained, the dentition model of the entity may be obtained by 3D printing, and thus, the step S101 is performed by obtaining the dentition model of the entity. It will be appreciated that these two embodiments are merely examples and that the dentition model 100 may be implemented as a numerical model or a physical model using other possible techniques known in the art.

As another example, for the shell appliance model 200: in one embodiment, based on the obtained digital dentition model 100, a digital shell appliance model 200 is obtained by assigning a predetermined thickness parameter to the next dentition layout state of the dentition model 100 in the orthodontic plan, and thus the step S101 is performed by obtaining the digital shell appliance model 200; in another embodiment, after obtaining the digital shell-shaped appliance model 200, a solid shell-shaped appliance model can be obtained by 3D printing and/or other forming techniques, and thus the step S101 is performed by obtaining the solid shell-shaped appliance model; in another embodiment, based on the digital dentition model 100, a positive mold is made according to the next dentition layout state of the dentition model 100 in the orthodontic plan, and then the solid shell appliance model 200 is obtained by laminating a film on the positive mold based on the hot-pressing film forming technique, so that the step S101 is also performed to obtain the solid shell appliance model 200. It will be appreciated that these three embodiments are merely exemplary and that the shell appliance model 200 may be implemented as a digital model or a physical model using other available techniques known in the art.

And S102, selecting a mounting point in the optional accessory mounting area on the dentition model, and constructing the retention accessory based on the mounting point.

In this step, as shown in fig. 2, for example, a mounting point P01 is selected from an attachment mounting optional area a1 on the dentition model 100, and the retention attachment 10 is constructed based on the mounting point P01 (reference numerals are shown in fig. 6).

Specifically, mounting point P01 is located within an attachment mounting optional area A1 (shown as a diagonal filled area in FIG. 2) on dentition model 100, which attachment mounting optional area A1 represents the tooth surface on the dentition that may be used to mount retention attachment 10, which is preferably a flat tooth surface.

In this embodiment, the mounting point P01 may be determined according to actual conditions, for example, in a preferred embodiment, the mounting point P01 may be determined by analyzing a large amount of historical cases of the bracket-free invisible appliance with big data, and using the location of the retention surface in the historical case where the retention effect is optimal (such as the frequency of accidental detachment of the appliance is minimum, or the retention force when the appliance is accidentally detached is maximum), which is, of course, merely an example, and in actual implementation, the mounting point P01 may be determined according to other factors or by other means.

Specifically, the step S102 further includes the following substeps.

And a substep S1021, taking off the shell-shaped appliance model worn on the dentition model from the dentition model, and acquiring the movement track of a reference point corresponding to the mounting point on the shell-shaped appliance model.

This sub-step S1021, as shown in fig. 2 to 4, for example, detaches the shell appliance model 200 worn on the dentition model 100 from the dentition model 100, and obtains the movement trajectory R of the reference point P02 corresponding to the mounting point P01 on the shell appliance model 200.

Specifically, referring to fig. 2, due to the matching relationship between dentition model 100 and shell appliance model 200, shell appliance model 200 has an accessory receiving slot selectable region a2 corresponding to the location of accessory mounting selectable region a1, and accessory receiving slot selectable region a2 represents a region of the shell appliance that may be used to position an accessory receiving slot (as shown below at 200 e' in fig. 6), while accessory receiving slot selectable region a2 has a datum point P02 corresponding to the location of mounting point P01.

In this sub-step S1021, the shell-shaped appliance model 200 is first worn on the dentition model 100, and it will be appreciated that, when worn intact, the attachment-receiving optional area a2 exactly completely overlaps the attachment-mounting optional area a1, and the reference point P02 exactly completely overlaps the mounting point P01.

Further, referring to fig. 4, the shell-shaped appliance model 200 is put from a state of being worn on the dentition model 100 (as indicated by a solid line in fig. 4) to a state of being detached from the dentition model 100 (as indicated by a broken line in fig. 4), and this process is defined for convenience as a detachment process in which the movement locus R of the reference point P02 is obtained during detachment.

Preferably, as shown in fig. 5, in the step of "acquiring a movement locus of a reference point on the shell-shaped appliance model corresponding to the mounting point": sequentially recording N coordinates (each coordinate is shown as a black point in FIG. 5) of the reference point P02 in a space coordinate system, wherein N is larger than or equal to 2, and sequentially fitting the N coordinates into a curve R, wherein the curve R forms the motion track R.

The "N coordinates" include the starting coordinate of the reference point P02, which is the coordinate of the reference point P02 when the shell appliance model 200 is worn on the dentition model 100. For example, as shown in fig. 5, N coordinates are exemplified by Pr1, … Prn, where Pr1 is the start coordinate of the reference point P02.

Here, in the spatial coordinate system X-Y-Z shown in fig. 5, the Y-axis is defined by the tooth major axis of the tooth 100a where the mounting point P01 is located, i.e., the Y-axis is parallel to the tooth major axis of the tooth 100a, and the Y-axis positive direction is defined in the direction from the gingival end to the occlusal end; a Z-axis positive direction is defined in a direction perpendicular to the long axis of the tooth 100a and from the lingual surface of the tooth 100a to the labial and buccal surface of the tooth 100 a; the X-axis positive direction is defined by a direction perpendicular to the long axis of the tooth 100a from the tooth 100a to the adjacent tooth 100b in front of the tooth 100a (or a direction from the mesial side to the mesial side of the tooth 100 a). Of course, fig. 5 is only an example of the spatial coordinate system of the present invention, and it is known in the art that the spatial coordinate system may be constructed in other directions as needed, and will not be described again.

Further, the step "sequentially records N coordinates of the reference point P02 in the spatial coordinate system", acquires the coordinates of the reference point P02 in the spatial coordinate system at intervals of time or at intervals of a certain displacement amount as the detachment process continues, starting from the start coordinate Pr1 of the reference point P02. Specifically, for example: in the sub-step S1021, the coordinates of the reference point P02 in the spatial coordinate system are recorded at intervals of time, such as 0.1S, thereby obtaining N coordinates Pr1, … Prn of the reference point P02 in the spatial coordinate system; alternatively, in the substep S1021, the coordinates of the reference point P02 in the spatial coordinate system are recorded at every constant displacement amount, and thereby the N coordinates Pr1 and … Prn of the reference point P02 in the spatial coordinate system are acquired.

And a substep S1022, establishing a tangent line of one key position point in the motion trail, or establishing a direct connection line of two key position points in the motion trail, and constructing the retention accessory according to a preset rule.

That is, in the sub-step S1022, a first auxiliary line is created based on the key position points in the motion trajectory R, and the retention attachment 10 is constructed according to the first auxiliary line.

Wherein, there are different implementations of the establishment of the first auxiliary line: for example, in one implementation, the first auxiliary line is a tangent line of a key position point in the motion trajectory R; in another implementation manner, the first auxiliary line is a direct connection line of two key position points in the motion trajectory R.

Preferably, the key position point is selected from a start position point, an end position point, and a transition position point, and of course, other position points may be selected as needed, which is not limited to this. Referring to fig. 5, the initial position point is the initial point of the motion trajectory R, i.e. the position point of the reference point P02 when the shell-shaped appliance model 200 is worn on the dentition model 100, such as the position point represented by the aforementioned coordinate Pr1, for convenience of description, the "initial position point" is denoted by Pr 1; the end position point, i.e., the position point Prt at which the reference point P02 is displaced from the projection space S of the normal F (see a dotted arrow in fig. 4) of the attachment installation selectable region a1, i.e., the end position point Prt is defined by an intersection of the boundary of the projection space S and the motion trajectory R; the transition position point, i.e., the position of the motion trajectory R between the start position point Pr1 and the end position point Prt, for example, as shown by the position point Prm in fig. 5.

Based on this, in the sub-step S1022, in an embodiment, if the "establishing a tangent line of a key position point in the motion trajectory" is performed, for example, the following may be specifically performed: a tangent to the starting position point Pr1 is established, as indicated by Q1 in fig. 5, or a tangent to the end position point Prt is established, as indicated by Q2 in fig. 5, or a tangent to the transition position point is established, as indicated by Q3 in fig. 5. Further, the first auxiliary line is a tangent line Q1, Q2, or Q3. Of course, when the key location point is selected from other location points, the established tangent line also changes accordingly, and is not enumerated.

In the sub-step S1022, in an embodiment, if the "establishing a straight line connecting two key position points in the motion trajectory" is implemented, for example, the following steps may be specifically performed: establishing a direct connection between the starting position point Pr1 and the ending position point Prt, as indicated by Q4 in fig. 5; a straight connection line (as exemplified by Q5 in fig. 5) may also be established between the starting position point Pr1 and the transition position point, or between the ending position point Prt and the transition position point. Further, the first auxiliary line is a straight line Q4 or Q5. Of course, when two key location points are selected from other location points, the established direct connection line also changes accordingly, and is not enumerated.

In the present embodiment, referring to fig. 6 to 7a, the retention fitting 10 generally includes a bottom surface 11, a retention surface 12 and a non-retention surface 13, which may be specifically configured as a closed three-dimensional body surrounded by the bottom surface 11, the retention surface 12 and the non-retention surface 13. Wherein the retention surface 12 includes a distal retention surface 121, a corner retention surface 122 and a gum-side retention surface 123 connected in series along a portion of the edge of the base 11 (i.e., edge P1-P2-P3-P4).

Further, in the substep S1022, when the retention accessory 10 is constructed, the rule one is satisfied: bottom surface 11 conforms to mating accessory mounting optional area a 1.

As previously mentioned, attachment mounting optional area A1 represents a tooth surface on the dentition that may be used to mount retention attachment 10; and correspondingly, the bottom surface 11, i.e., the mounting surface of the retention attachment 100, is intended to be attached to the teeth. As such, retention attachment 10 is constructed based on the rules described above, i.e., bottom surface 11 is designed to mate with attachment mounting optional area a1 to facilitate snug attachment through bottom surface 11 at the tooth surface corresponding to attachment mounting optional area a 1.

It will be appreciated that in one embodiment, in the embodiment of attachment to a tooth, the bottom surface 11 may be adhesively secured snugly against the tooth surface corresponding to the attachment mounting alternative area a 1.

Further, in the sub-step S1022, when the retention accessory 10 is constructed, the rule two is also satisfied: the intersection line P3-P4 of the gum side retention surface 123 and the bottom surface 11 is a first straight line, the intersection line P3-P5 of the corner retention surface 122 has a highest point P5 in the normal direction of the bottom surface 11, and a plane defined by the first straight line (the intersection line P3-P4) and the highest point P5 forms an included angle of 60-90 degrees with the first auxiliary line; alternatively, the intersection line P3-P5 between the gum side retention surface 123 and the corner retention surface 122 is a second straight line, the intersection line P3-P4 between the gum side retention surface 123 and the bottom surface 11 has a farthest point P4 away from the corner retention surface 122, and a plane defined by the second straight line (the intersection line P3-P5) and the farthest point P4 forms an included angle of 60-90 degrees with the first auxiliary line.

In detail, the gum side retention surface 123 and the bottom surface 11 have an intersection line P3-P4; the gum side retention surface 123 and the corner retention surface 122 have an intersection line P3-P5.

On the intersection line P3-P4, the point P4 is the farthest point from the corner retention surface 122 and the farthest point from the intersection line P3-P5, and the point P3 is the closest point to the corner retention surface 122 (i.e., the point P3 is the intersection point of the intersection line P3-P4 and the corner retention surface 122) and the intersection point (or common point) from the intersection line P3-P5. Similarly, point P5 is the highest point of intersection P3-P5 in the normal direction of bottom surface 11 and the farthest point from intersection P3-P4, and point P3 is the lowest point of intersection with bottom surface 11 (i.e., point P3 is the intersection of intersection P3-P5 with bottom surface 11), on intersection P3-P5.

In this sub-step S1022, in one embodiment, the second rule may be that the intersection line P3-P4 is a straight line, and the plane defined by the intersection line P3-P4 and the point P5 forms an angle of 60 ° to 90 °, preferably 90 °, with the first auxiliary line (for example, the tangent line Q1 or Q2 or Q3, or the straight line Q4 or Q5), so that the gum-side retention surface 123 of the retention attachment 10 is constructed based on the second rule; alternatively, the second rule may be that the intersection line P3-P5 is a straight line, and the plane defined by the intersection line P3-P5 and the point P4 forms an angle of 60 to 90 degrees, preferably 90 degrees, with the first auxiliary line (for example, the tangent line Q1 or Q2 or Q3, or the straight line Q4 or Q5), so that the gingival side retention surface 123 of the retention attachment 10 is constructed on the basis of the second rule.

Thus, the method of constructing the present invention constructs the bottom surface 11 based on the attachment mounting selectable region a1 and constructs the gingival-side retention surface 123 based on the first auxiliary line, such that the retention attachment 10 of an embodiment can greatly improve the retention force of the appliance 200' compared to the prior art, and solve the problem of the prior art that the appliance is easy to fall off due to insufficient retention force of the retention attachment to the appliance.

In the present embodiment, as shown in the figure, the gum side retention surface 123 is designed as a plane having an angle of 60 ° to 90 ° with respect to the first auxiliary line, and particularly preferably has an angle of 90 ° (i.e. the gum side retention surface 123 is perpendicular to the first auxiliary line); the intersecting line P3-P4 is a straight line. Of course, in alternative embodiments of the present invention, the gingival-side retention surface 123 may be designed to have a concave curvature that satisfies the second rule, as shown in FIG. 10a for example 3, FIG. 11a for example 4, and FIG. 14a for example 7, or may be designed to have a convex curvature that satisfies the second rule, as shown in FIG. 12a for example 5, and FIG. 13a for example 6, as described in detail below.

Further, in a preferred embodiment, in step S102, the attachment mounting optional area a1 is located on the labial surface of the dentition model 100, and correspondingly, the attachment receiving groove optional area a2 is located on the labial surface of the shell-shaped appliance model 200.

Correspondingly, the shell-shaped appliance model to be worn on the dentition model is preferably detached from the dentition model: and taking the lingual side of the shell-shaped appliance model as an action area of an actuating force, and taking off the shell-shaped appliance model worn on the dentition model from the dentition model by adopting the actuating force.

Thus, the action area of the actuating force is selected at the lingual side of the shell-shaped appliance model 200, and the shell-shaped appliance model 200 is taken off based on the action area, so that the constructed retention accessory can improve the retention effect, and particularly, when the tongue licks and presses the tongue of the patient accidentally and other causes occur, the accidental falling of the appliance is avoided.

Here, it is understood that the "actuation force application zone" is the point at which the actuation force is initiated in the shell appliance model 200. Preferably, in one embodiment, the gingival margin on the lingual side of the shell appliance model 200 is used as the action region of the actuating force, and particularly, as shown in the figure, the gingival margin midpoint on the lingual side of the distal molar shell unit 200a of the shell appliance model 200 is used as the action region of the actuating force.

Of course, in alternative implementations, the region of action of the actuating force is not limited to the lingual gingival margin, nor to the distal molar shell unit 200a, and other suitable locations of the shell appliance model 200 (e.g., on the penultimate molar shell 200 b) may be used as the region of action of the actuating force, and are not enumerated.

In the specific implementation: when the dentition model 100 and the shell-shaped appliance model 200 are respectively implemented as solid models, a force can be applied to the lingual side of the shell-shaped appliance model 200 by a tensile testing machine so as to detach the shell-shaped appliance model 200 worn on the dentition model 100 from the dentition model 100; alternatively, when the dentition model 100 and the shell-shaped appliance model 200 are implemented as digital models, the actuation force may be modeled using a simulation technique to detach the shell-shaped appliance model 200, which is worn on the dentition model 100, from the dentition model 100.

Further, the attachment mounting selectable area a1 is also located on any one, two or more of the molars and premolars of the dentition model 100. While the attached optional area a1 is illustrated in the drawings as being located on the last molar tooth (i.e., tooth 100a) of the dentition model 100 for the purpose of explaining the construction method of the present embodiment, the tooth on which the attached optional area a1 is located is not limited thereto in the actual implementation.

It will be appreciated that the attachment receiving slot optional region a2 is located on any one, two or more of the molar shell unit of the corresponding molar and the premolar shell unit of the corresponding premolar of the shell appliance model 200 corresponding to the location of the attachment mounting optional region a 1. For the purpose of illustrating the construction method of this embodiment, the drawings illustrate only the attachment receiving slot optional area a2 on the distal molar shell unit 200a of the shell appliance model 200. In addition, the actuating force is a vector parameter, and in one embodiment, the actuating force has a component pointing to the occlusal end along the long axis of the tooth and a component pointing to the labial and buccal surfaces perpendicular to the long axis of the tooth, that is, the direction of the actuating force is-a non-zero included angle is formed with the long axis of the tooth 100a where the optional area a1 for attachment installation is located, the included angle is pointed to the occlusal end from the gingival end and is pointed to the labial and buccal surfaces from the lingual surfaces at the same time, so that the retention attachment constructed based on the actuating force can further avoid the situation that the appliance falls off due to the licking pressure of the tongue, and the retention effect on the appliance is greatly improved. Of course, in an alternative embodiment, the actuating force may also be directed along the long axis of the tooth toward the occlusal end, i.e., it may be directed along the long axis of the tooth 100a where the attachment mounting optional area a1 is located toward the occlusal end of the tooth 100 a.

Further, with respect to the intersection line P3-P4 of the gingival-side retention surface 123 and the bottom surface 11, on a projection plane along the normal direction of the bottom surface 11, the straight line connecting the point P3 and the point P4 forms an angle of 60 DEG-90 DEG with the long axis of the tooth 100a where the attachment mounting optional region A1 is located. That is, on a projection plane normal to the bottom surface 11, a straight line of the point P3 and the point P4 may be: perpendicular to the long axis of the tooth 100a where the attachment mounting selectable area a1 is located; or, from the point P3 to the point P4, the tooth is extended from the tooth 100a to approach the occlusal surface of the tooth 100a in a state of an acute included angle of more than or equal to 60 degrees with the tooth major axis of the tooth 100a in which the optional accessory mounting area A1 is located; alternatively, the tooth 100a may be approached from point P3 to point P4 at an acute angle of 60 degrees or more from the long axis of the tooth 100a where the optional attachment mounting area A1 is located.

Further, the distal retention surface 121 has an intersection line P1-P2 with the bottom surface 11 and an intersection line P2-P6 with the corner retention surface 122.

On the intersection line P1-P2, point P1 is the farthest point from the corner retention surface 122 and also the farthest point from the intersection line P2-P6, and point P2 is the closest point to the corner retention surface 122 (i.e., point P2 is the intersection point of the intersection line P2-P6 and the corner retention surface 122) and also the intersection point (or common point) with the intersection line P2-P6. Similarly, point P6 is the highest point of intersection P2-P6 in the normal direction of bottom surface 11 and the farthest point from intersection P1-P2, and point P2 is the lowest point of intersection with bottom surface 11 (i.e., point P2 is the intersection of intersection P2-P6 with bottom surface 11), on intersection P2-P6.

Preferably, in this sub-step S1022, with reference to fig. 7b, when the retention accessory 10 is constructed, rule three is also satisfied: on a projection plane along the normal direction of the bottom surface 11, an included angle k0 between a straight line from a point P2 to a point P1 and a straight line from a point P3 to a point P4 is 60-120 degrees.

It can be understood that the rule three includes three different implementations: first, in the embodiment shown in FIG. 7b, k0 has an acute angle of 60 ° or more on the projection plane along the normal direction of the bottom surface 11; secondly, as shown in fig. 7c, as a simple variation of fig. 7b, k0 is at a right angle on a projection plane along the normal of the bottom surface 11; thirdly, as shown in FIG. 7d, as a further simple variation of FIG. 7b, k0 has an obtuse angle of 120 ° or less on a projection plane along the normal direction of the bottom surface 11.

Thus, on the basis of the rule one and the rule two, the retention attachment 10 is further constructed according to the rule three, specifically, the distal retention surface 123 of the retention attachment 10 is constructed based on the rule two, so that the retention attachment 10 has a wedge-shaped structure, and the retention effect on the appliance 200 'is further enhanced, so that the appliance 200' can be more and more compressed with the retention attachment 10 in the accidental uncapping movement.

Further, with respect to the intersection line P1-P2 of the distal retention surface 121 and the bottom surface 11, on a projection plane along the normal direction of the bottom surface 11, the straight line connecting the point P1 and the point P2 forms an angle of 0 to 45 degrees with the major axis of the tooth 100a in which the attachment mounting optional region A1 is located. That is, on a projection plane normal to the bottom surface 11, a straight line of the point P1 and the point P2 may be: parallel to the long axis of the tooth 100a where the attachment mounting selectable area a1 is located; or, the tooth attachment mounting optional region A1 extends forwards (i.e. towards the medial side of the tooth 100a) from the point P2 to the point P1 in a state of forming an acute included angle of less than or equal to 45 degrees with the long axis of the tooth 100 a; alternatively, the angle from point P2 to point P1 extends rearwardly (i.e., toward the distal side of the tooth 100a) at an acute angle of 45 ° or less with respect to the long axis of the tooth 100a in which the attachment mounting selectable region A1 is located.

Further, in the present embodiment, as illustrated in the drawings, the distal retention surface 121 is designed as a flat surface that is in line with the bottom surface 11 at an intersection line P1-P2. Of course, in alternative embodiments of the present invention, the distal retention surface 121 may be designed as a concave surface satisfying the third rule, as shown in example 3 in fig. 10a, example 6 in fig. 13a, and example 7 in fig. 14a, or as a convex surface satisfying the third rule, as shown in example 4 in fig. 11a, and example 5 in fig. 12a, which will be described in detail later.

In one embodiment, the corner retention surface 122 and the bottom surface 11 have an intersection line P2-P3; preferably, the step S102 further includes a sub-step S1023: and establishing a second auxiliary line different from the first auxiliary line, wherein the second auxiliary line is a tangent line of one key position point or a direct connection line of two key position points in the motion trail.

Wherein, similar to the first auxiliary line, there are also different implementations of the establishment of the second auxiliary line: for example, in one implementation, the second auxiliary line is a tangent line of a key position point in the motion trajectory R; in another implementation manner, the second auxiliary line is a direct connection line of two key position points in the motion trajectory R; also, in the establishment of the second auxiliary line, the key position point may be selected from the start position point, the end position point, the transition position point, or another position point as needed.

Whereas, considering that the second auxiliary line is different from the first auxiliary line, it means that:

if the first auxiliary line is a tangent line of a certain key position point, the second auxiliary line may be a tangent line of another key position point, or may be a straight connecting line of two key position points, and for example, in fig. 5, if the first auxiliary line is a tangent line Q1, the second auxiliary line may not be a tangent line Q14 but may be a tangent line Q2, a tangent line Q3, a straight connecting line Q4, a straight connecting line Q5, or the like;

if the first auxiliary line is a tangent line of two key position points, the second auxiliary line may be a straight line of two other key position points, or may also be a tangent line of one key position point, and taking fig. 5 as an example, for example, if the first auxiliary line is a straight line Q4, the second auxiliary line may not be a straight line Q4 but may be a tangent line Q1, a tangent line Q2, a tangent line Q3, or a straight line Q5.

In sub-step S1023, the retention accessory 10 also satisfies rule four: the plane S2 defined by the end point P2, the end point P3 and the point P5 of the intersection line P2-P3 forms an angle of 60-90 degrees, preferably 90 degrees, with the second auxiliary line. In this way, the retention attachment 10 is constructed based on the second auxiliary line, and particularly the corner retention surface 122 of the retention attachment 10 is constructed, so that the retention force of the retention attachment 10 on the appliance 200' can be further enhanced, and the problem that the appliance is easy to fall off due to insufficient retention force of the retention attachment on the appliance in the prior art is solved. In the preferred embodiment, the corner retention surface 122 is designed to be convexly curved, in particular convexly curved, in a cross-section perpendicular to the normal of the bottom surface 11, as illustrated in the figure. Of course, the shape of the corner retaining surface 122 is not limited to this, and may be a plane having an angle of 60 ° to 90 ° with the second auxiliary line.

Further, in a preferred embodiment, the first auxiliary line is a tangent line Q1 of the initial position point Pr1, and the second auxiliary line is a straight line Q4 of the initial position point Pr1 and the final position point Prt, so that the position of the gingival side retention surface 123 of the retention accessory 10 is designed based on the tangent line Q1 of the initial position point Pr1, and the position of the corner retention surface 122 of the retention accessory 10 is designed based on the straight line Q4 of the initial position point Pr1 and the final position point Prt, so as to further enhance the retention force and ensure the retention effect of the retention accessory 10 on the appliance 200'.

Further, referring to FIG. 7a, the retention surface 12 extends from a portion of the edge of the bottom surface 11 (specifically, the edge P1-P2-P3-P4) gradually away from the bottom surface 11 until reaching an upper edge 12a of the retention surface 12, the upper edge 12a defining the maximum height of the retention attachment 10 normal to the bottom surface 11. In the present embodiment, the maximum height of the retention attachment 10 in the normal direction of the bottom surface 11 is defined by the upper edge 122a of the corner retention surface 122, and the point T in the upper edge 122a is exemplified as the maximum height point of the retention attachment 10 in the normal direction of the bottom surface 11. Of course, in alternative implementations, the point of maximum height T may also be located in the upper edge 123a of the gingival-side retention surface 123 or in the upper edge 121a of the distal-side retention surface 121.

Preferably, the distal retention surface 121, the corner retention surface 122 and the gum retention surface 123 may be respectively configured as: and is arranged at an included angle of 60-120 degrees with the bottom surface 11. In other words, the distal retaining surface 121, the corner retaining surface 122 and the gum retaining surface 123 extend away from the bottom surface 11 along a straight line at an included angle of 60 ° to 120 ° with respect to the bottom surface 11. Thus, the retention surface 12 may provide greater retention force to the appliance 200 ', resulting in retention of the appliance 200 ' on the dentition 100 '. Further, the angle of the included angle herein may preferably be 60 ° to 90 °, and more preferably 75 ° to 90 °. In addition, in a variant implementation, the distal retention surface 121, the corner retention surface 122 and the gum retention surface 123 may also be respectively arranged to extend away from the bottom surface 11 along a curve, as in the embodiment shown in fig. 14 a; furthermore, in various embodiments, one or two of the distal retention surface 121, the corner retention surface 122 and the gum retention surface 123 may be configured to extend away from the bottom surface 11 along a straight line (as shown in the embodiment or any one of fig. 9 a-13 b), and the rest of the three may be configured to extend away from the bottom surface 11 along a curved line (as shown in fig. 14 a), without departing from the spirit of the present invention.

In the present embodiment, referring to fig. 7b and 7c, the distal retaining surface 121, the corner retaining surface 122 and the gum retaining surface 123 are perpendicular to the bottom surface 11 (i.e. parallel to the normal of the bottom surface 11), such as the included angle k1 is a right angle in fig. 7c, i.e. extending along a straight line perpendicular to the bottom surface 11. Thus, in combination with the above, the distal retaining surface 121 and the gum retaining surface 123 are both planes perpendicular to the bottom surface 11, and the corner retaining surface 122 is a cylindrical arc surface perpendicular to the bottom surface 11.

In addition, in this embodiment, the retention attachment 10 may further include an anti-slip structure added on the retention surface 12, and the anti-slip structure may be any one or a combination of a plurality of protrusions, a plurality of pits, and one or a plurality of indentations, so as to enhance the friction force between the retention attachment 10 and the appliance and ensure the retention effect of the appliance.

Further, the non-retention surface 13 does not play a retention role for the appliance 200 ' on the dentition 100 ', its relationship with the bottom surface 11 is more gradual than the relationship of the retention surface 12 with the bottom surface 11, and the configuration of the non-retention surface 13 facilitates the smooth seating of the guiding appliance 200 ', for example, the receiving groove 200e ' of the guiding appliance 200 ' is smoothly caught at the retention attachment 10, so the non-retention surface 13 may also be referred to as a guiding surface.

The non-retention surface 13 extends obliquely downward from the upper edge 12a of the retention surface 12 until it is connected to the edge P1-P4 of the bottom surface 11 (i.e., the remaining portion of the peripheral edge of the bottom surface 11 excluding the edge P1-P2-P3-P4). Preferably, the non-retention surface 13 is provided with a convex curved surface, and the tangent plane at any position thereof makes an angle k2 of less than 60 ° with the bottom surface 11.

Further, the present embodiment also provides a construction system of the retention attachment corresponding to the construction method shown in fig. 1.

The construction system comprises a memory and a processor, the memory stores a computer program which can run on the processor, and the processor executes the computer program to realize the steps of the construction method.

Here, the processor of the construction system will be briefly described with reference to fig. 1 to 5. The processor includes an acquisition unit, a control unit, and a processing unit.

The acquiring unit is used for acquiring a dentition model 100 and a shell-shaped appliance model 200 matched with the dentition model 100; the control unit is used for controlling the shell-shaped appliance model 200 worn on the dentition model 100 to be detached from the dentition model 100; the acquiring unit is also used for acquiring the movement track R of a reference point P02 corresponding to the mounting point P01 on the shell-shaped appliance model 200 in the process of taking off the shell-shaped appliance model 200 worn on the dentition model 100 from the dentition model 100; the processing unit is configured to establish tangents (such as tangents Q1, Q2, and Q3 in fig. 5) of one key position point in the motion trajectory R, or establish a straight connection (such as straight connections Q4 and Q5 in fig. 5) of two key position points in the motion trajectory R, and construct the retention accessory 10 according to the above rules.

It should be noted that each unit of the processor may be further configured to perform detailed implementation of the corresponding step in the aforementioned construction method and other steps, which may be referred to specifically for the aforementioned description and will not be described herein again.

Further, corresponding to the building method shown in fig. 1 to 5, the present embodiment also provides a computer-readable storage medium, on which a computer program is stored, which when executed by a processor implements the steps in the building method described above. Details are not repeated.

The bracket-free invisible orthodontic appliance of the embodiment is described in detail below with reference to the foregoing and fig. 6 to 8 b.

The bracket-free invisible appliance includes a shell-shaped appliance 200' and the retention attachment 10 described above.

It is understood that the appliance 200 'has a structure and a shape corresponding to the shell appliance model 200 in the construction method, and the accommodating groove 200 e' is added on the basis of the shell appliance model 200.

The retention attachment 10 is constructed using the construction method described above and is fixedly attached to the tooth surface of the dentition 100 ' by its bottom surface 11 for providing a retention force to the appliance 200 ' fitted to the dentition 100 '. In particular embodiments, the bottom surface 11 may be affixed to the tooth surface by means of an adhesive.

The cavity of the appliance 200 ' may receive the dentition 100 ', and it will be appreciated that the appliance 200 ' is divided into shell units that fit the individual tooth shapes on the dentition 100 ', for example, corresponding to the last molar (hereinafter second molar 100a '), the appliance 200 ' has a shell unit 200a ', and the cavity of the shell unit 200a ' may just receive the last molar 100a '.

The appliance 200 'also has an attachment receiving slot 200 e', which attachment receiving slot 200e 'communicates with the internal cavity of the appliance 200' and can receive the retention attachment 10. When the appliance 200 'is installed on the dentition 100', the non-retention surface 13 of the retention attachment 10 is beneficial to guiding the appliance 200 'to be smoothly positioned, so that the attachment accommodating groove 200 e' of the appliance 200 'is smoothly clamped at the retention attachment 10, that is, the retention attachment 10 is embedded in the attachment accommodating groove 200 e'; when the appliance 200 ' is held on the dentition 100 ', i.e., in the installed state, the retention surfaces 12 of the retention attachments 10 may abut against the groove surfaces of the attachment receiving grooves 200e ' to prevent the appliance 200 ' from being separated from the dentition 100 '.

Referring to fig. 8a and 8b, the gum-side retention surface 123 of the retention surface 12 abuts against the gum-side groove surface 2003e ' of the receiving groove 200e ', which is the groove surface of the receiving groove 200e ' on the side close to the gum; the distal retention surface 121 of the retention surface 12 abuts the distal slot surface 2001e 'of the receiving slot 200 e', the distal slot surface 2001e ', i.e. the receiving slot 200 e', being adjacent to the distal slot surface; the corner retaining surface 122 of the retaining surface 12 abuts against the corner groove surface 2002e ' of the receiving groove 200e ', and both ends of the distal groove surface 2001e ' connect the gum side groove surface 2003e ' and the distal groove surface 2001e '. As can be seen from the above-mentioned construction method, the bottom surface 11 of the retention attachment 10 matches the surface of the tooth 100 a' on which the retention attachment 10 is mounted, and the gingival-side retention surface 123 forms an angle of 60 DEG to 90 DEG with the first auxiliary line (e.g., the tangent line Q1, or Q2, or Q3 in FIG. 5) or the straight line (e.g., the straight line Q4 in FIG. 5). Thus, in one embodiment of the present invention, the retention force of the retention attachment 10 on the appliance 200' is greatly improved compared to the prior art, and the problem of the prior art that the appliance is easy to fall off due to insufficient retention force of the retention attachment on the appliance is solved.

Further, the appliance 200 ' includes a buccal labial shell 200d ' and a lingual shell 200c '. When the appliance 200 'is installed on the dentition 100', the labial shell 200d 'is positioned on the labial side of the dentition 100', and the lingual shell 200c 'is positioned on the lingual side of the dentition 100'.

And an attachment receiving recess 200e 'is provided in the labial cheek-side housing 200 d' and is located in any one or more of several housing units corresponding to molars and premolars on the appliance 200 ', for example, the appliance 200' shown in fig. 6 has a housing unit 200b 'corresponding to the first molar 100 b' (hereinafter referred to as "first molar housing unit 200b '" for ease of understanding), a housing unit 200 a' corresponding to the second molar 100a '(hereinafter referred to as "second molar housing unit 200 a'" for ease of understanding), a housing unit corresponding to the first premolar (hereinafter referred to as "first premolar housing unit for ease of understanding), and a housing unit corresponding to the second premolar (hereinafter referred to as" second premolar housing unit for ease of understanding) among the first molar housing unit, the second molar housing unit 100a, the first premolar housing unit, the second molar housing unit 100a, the first premolar housing unit, Any one or any two or more of the second premolar housing units are provided with accessory receiving slots 200e ', it being understood that corresponding teeth are also provided with retention accessories 10 which mate with the respective accessory receiving slots 200 e'. Of course, in alternative implementations, for dentitions having a third molar, the appliance 200 'may have a corresponding third molar shell unit in which the accessory receiving slot 200 e' is located.

Preferably, as shown in fig. 6, the attachment receiving groove 200e ' is located at the housing unit 200a ' of the appliance 200 ' corresponding to the last molar (i.e., the second molar 100a ' in fig. 6), that is, referring to fig. 6, the attachment receiving groove 200e ' is provided at the labial side of the housing unit 200a ', and more preferably, at the central region of the labial side of the housing unit 200a '. It will be appreciated that the retention attachment 10 is also mounted on the labial and buccal surfaces of the last molars (i.e., second molars 100a ' in fig. 6) of the dentition 100 ' corresponding to the location of the attachment receiving slot 200e '. Thus, in view of the situation that the retention attachment is adhered to the labial and buccal surfaces of the teeth mentioned in the background art, the retention function of the retention attachment 10 on the appliance 200 'is greatly improved, and the appliance 200' is prevented from being accidentally dropped when the tongue of the patient is accidentally pressed and the like.

Still preferably, the attachment receiving slot 200e 'may also be located on the shell unit 200 b' of the appliance 200 'corresponding to the last second tooth (i.e., the first molar 100 b' in fig. 6). That is, referring to fig. 6, the accessory receiving groove 200e ' is provided at a labial side of the housing unit 200b ', and more preferably, at a distal region of the labial side of the housing unit 200b '.

Further, based on the correspondence of the dentition model 100 and the dentition 100':

with reference to the foregoing orientation relationship between the straight line connecting point P1 and point P2 and the long axis of the tooth 100a in which the optional attachment mounting region a1 is located, it can be determined that, with reference to fig. 8a, on the projection plane along the normal to the bottom surface 11, the straight line connecting point P1 and point P2 makes an angle of 0 ° to 45 ° with the long axis V1 of the tooth (e.g., 100a ', 100 b' in fig. 6) in which the retention attachment 10 is located;

with reference to the foregoing orientation relationship between the straight line connecting point P3 and point P4 and the long axis of tooth 100a in which the optional attachment mounting region A1 is located, it can be determined that, with reference to FIG. 8a, on a projection plane along the normal to the bottom surface 11, the straight line connecting point P3 and point P4 makes an angle of 60 DEG to 90 DEG with the long axis V1 of the tooth (e.g., 100a ', 100 b' in FIG. 6) in which the retention attachment 10 is located.

Further, a distal groove surface 2001e 'of the receiving groove 200 e' has a shape matching an intersection line P1-P2 of the distal retention surface 121 and the bottom surface 11; further, referring to fig. 8b, on the projection plane along the normal direction of the bottom surface 11, the straight connection line of the two end points 20012e ', 20011 e' of the far-middle side slot surface 2001e 'forms an included angle of 0 ° to 45 ° with the tooth major axis V of the housing unit (e.g., 200 a', 200b 'in fig. 6) where the accommodation slot 200 e' is located. In this embodiment, the distal groove surface 2001e ' extends linearly from the end point 20012e ' to the end point 20011e '.

Similarly, the gingival side groove surface 2003e 'of the receiving groove 200 e' has a shape matching the intersection line P3-P4 of the gingival side retention surface 123 and the bottom surface 11; further, referring to fig. 8b, on the projection plane along the normal direction of the bottom surface 11, the straight connection line of the two end points 20033e 'and 20034 e' of the gum side groove surface 2003e 'forms an included angle of 60 ° to 90 ° with the tooth major axis V of the shell unit (e.g., 200 a' and 200b 'in fig. 6) where the receiving groove 200 e' is located. In the present embodiment, the gum-side groove surface 2003e ' extends linearly from the end point 20033e ' to the end point 20034e '.

Furthermore, the corner groove surface 2002e 'of the receiving groove 200 e' has a shape matching the intersection line P3-P2 of the corner fixing surface 122 and the bottom surface 11, which is a circular arc in the present embodiment.

In summary, the present embodiment has the following beneficial effects:

(1) the bottom surface 11 is constructed on the basis of the attachment installation optional area A1, and the gingival side retention surface 123 is constructed on the basis of the first auxiliary line, so that the retention force of the retention attachment 10 on the appliance 200' can be greatly improved, and the problem that the appliance is easy to fall off due to insufficient retention force of the retention attachment on the appliance in the prior art is solved;

(2) the action area of the actuating force is selected at the lingual side of the shell-shaped appliance model 200, and the taking-off process of the shell-shaped appliance model 200 is implemented on the basis, so that the retention function of the constructed retention accessory 10 during lingual side sleeve removal can be further improved, and accidental falling of the appliance is avoided when the inducement such as the accidental tongue licking pressure of a patient occurs;

(3) in addition, a series of design schemes such as the design of the angle relationship between the corner retaining surface 122, each retaining surface and the bottom surface 11, the design of the angle relationship between the intersection line P1-P2 on the far-middle retaining surface 121 and the intersection line P3-P4 on the gum-side retaining surface 123 and the like are constructed based on the second auxiliary line, so that the self structure of the retaining accessory 10 is further optimized and/or the arrangement and orientation of the retaining accessory 10 on the teeth are optimized, the sufficient retaining effect of the appliance is ensured, and the retaining advantages of the appliance are more obvious compared with the existing accessories especially for patients with short crown length, such as the patients with small age.

Example 2

Referring to fig. 9a to 9c, a preferred embodiment 2 of the present invention is illustrated, which is different from the foregoing embodiment 1 only in that: the angles between the distal retaining surface 221, the corner retaining surface 222 and the gum retaining surface 223 and the bottom surface 21 are different from those illustrated in fig. 7a of embodiment 1. Only the technical contents related to the difference point will be described below, and the rest of the technical contents that are the same as those in embodiment 1 will not be described again.

As shown in FIG. 7a of the previous embodiment 1, the distal retaining surface 121, the corner retaining surface 122 and the gum retaining surface 123 are perpendicular to the bottom surface 11, i.e., the angle k1 between the retaining surface 12 and the bottom surface 11 is 90 °.

In the embodiment 2, the included angles between the distal retaining surface 221, the corner retaining surface 222, and the gum retaining surface 223 and the bottom surface 21 are acute angles of 60 ° or more, that is, the distal retaining surface 221, the corner retaining surface 222, and the gum retaining surface 223 extend linearly at acute included angles of 60 ° or more with the bottom surface 21. Thus, in this embodiment, as shown in embodiment 1, the distal retaining surface 221 and the gum retaining surface 223 are both flat surfaces, and the corner retaining surface 122 is a cylindrical arc surface.

Examples 3 to 6

First, referring to fig. 10a to 10b, a preferred embodiment 3 of the present invention is illustrated, which is different from the foregoing embodiment 1 only in that: the configuration of the distal retaining surface 521 and the gingival retaining surface 523. Only the technical contents related to the difference point will be described below, and the rest of the technical contents that are the same as those in embodiment 1 will not be described again.

In the above-described embodiment 1, the distal-medial-side retention surface 121 and the gingival-side retention surface 123 are both flat; furthermore, the intersection line P1-P2 between the distal retaining surface 121 and the bottom surface 11 and the intersection line P3-P4 between the gum retaining surface 123 and the bottom surface 11 are all straight.

In the present embodiment 3, referring to fig. 10a to 10b, the distal retaining surface 521 and the gingival retaining surface 123 are respectively designed as concave curved surfaces.

Specifically, the intersection lines P2-P6 of the distal retention surface 521 and the corner retention surface 522 are straight lines, and the intersection lines P1-P2 with the bottom surface 51 are concave curves, such that the distal retention surface 521 is designed as a concave curve extending perpendicularly to the bottom surface 51 from the intersection lines P1-P2.

Similarly, the intersection line P3-P5 of the gum side retaining surface 532 with the corner retaining surface 522 is a straight line, and the intersection line P3-P4 with the bottom surface 51 is a concave curve, so that the gum side retaining surface 532 is constructed based on the second rule, the plane S1 defined by the intersection line P3-P5 and the point P4 forms an angle of 60-90 degrees with the first auxiliary line, and on this basis, the gum side retaining surface 532 is designed as a concave curve extending perpendicularly to the bottom surface 51 from the intersection line P3-P4.

Of course, in the above embodiment 3, the intersection line P1-P2 of the distal retention surface 521 and the bottom surface 51 is a concave curve, and the intersection line P3-P4 of the gum-side retention surface 532 and the bottom surface 51 is a concave curve, but the invention is not limited thereto: for example, refer to embodiment 4 illustrated in FIGS. 11 a-11 b, which is modified from embodiment 3 in that the intersection line P1-P2 of the distal retention surface 621 and the bottom surface 61 is a convex curve; for another example, see the embodiment 5 illustrated in fig. 12 a-12 b, which is modified based on the embodiment 3 in that the intersection line P1-P2 of the distal retention surface 721 and the bottom surface 71 and the intersection line P3-P4 of the gingival retention surface 732 and the bottom surface 71 are both convex curves; for another example, refer to the embodiment 6 illustrated in fig. 13a to 13b, which is modified from the embodiment 3 in that the intersection line P3-P4 of the gum-side retention surface 832 and the bottom surface 81 is a convex curve.

Of course, in the embodiments 3-6, each of the distal retention surfaces and each of the gingival retention surfaces are exemplified as extending perpendicular to the bottom surface, and in a variation, each of the distal retention surfaces and each of the gingival retention surfaces may be variably designed to be disposed at any other included angle between 60 ° and 120 ° with the bottom surface, that is, each of the distal retention surfaces and each of the gingival retention surfaces may extend along a straight line at an included angle between 60 ° and 120 ° with the bottom surface.

Example 7

Referring to fig. 14a to 14c, a preferred embodiment 7 of the present invention is illustrated, which is different from the foregoing embodiment 1 only in that: the distal retention surface 1121, the gingival retention surface 1123. Only the technical contents related to the difference point will be described below, and the rest of the technical contents that are the same as those in embodiment 1 will not be described again.

As mentioned in the foregoing embodiment 1, the distal retaining surface 121, the corner retaining surface 122 and the gum retaining surface 123 may be disposed at an angle of 60 ° to 120 ° with respect to the bottom surface 11, in other words, the distal retaining surface 121, the corner retaining surface 122 and the gum retaining surface 123 extend linearly at an angle of 60 ° to 120 ° with respect to the bottom surface 11.

In the present embodiment 7, referring to fig. 14a to 14c, the distal retention surface 1121, the corner retention surface 1122 and the gum retention surface 1123 are respectively configured to extend from the bottom surface 111 to the upper edge 112a along a curve that is concave from the intersection with the bottom surface 111.

Specifically, the intersection line P3-P4 of the gingival-side retention surface 1123 and the bottom surface 111 is a straight line, the gingival-side retention surface 1132 is constructed based on the second rule, the plane S1 defined by the intersection line P3-P4 and the point P5 forms an included angle of 60-90 DEG with the first auxiliary line, and on this basis, the gingival-side retention surface 532 is designed as a concave curved surface extending away from the bottom surface 111 in a concave curve from the intersection line P3-P4.

And further, a plane S1 defined by the intersection line P3-P4 and the point P5 is also provided as: is arranged at an angle of 60 deg. -120 deg. to the bottom surface 111, where the angle may preferably be 60 deg. -90 deg., and more preferably 75 deg. -90 deg., illustrated in the figure as being 90 deg. (i.e. the straight line of point P5 and point P3 is perpendicular to the bottom surface 111).

Further, the intersection line P2-P1 between the distal retention surface 1121 and the bottom surface 111 is a straight line, and the distal retention surface 1121 is designed to be a concave curve extending away from the bottom surface 111 in a concave curve from the intersection line P2-P1. And the plane defined by the intersection line P2-P1 and the point P6 is also set as follows: is arranged at an angle of 60 deg. -120 deg. to the bottom surface 111, where the angle may preferably be 60 deg. -90 deg., and more preferably 75 deg. -90 deg., illustrated in the figure as being 90 deg. (i.e. the straight line of point P6 and point P2 is perpendicular to the bottom surface 111).

In addition, likewise, the corner retention surface 1122 is configured to extend away from the bottom surface 111 in a concave curve from the intersection P2-P3 with the bottom surface 111. And, a plane S2 defined by the point P2, the point P3, and the point P5 is set as: arranged at an angle of 60 deg. -120 deg. to the bottom surface 111, where the angle may preferably be 60 deg. -90 deg., and more preferably 75 deg. -90 deg., exemplified in the figures as being 90 deg..

It should be noted that, although the exemplary retention accessories of the embodiments shown in fig. 9a to 14c are slightly different from those shown in embodiment 1, the retention accessories may be constructed and molded by the construction method and the construction system disclosed in embodiment 1, and may also be used to retain the appliance adapted thereto, wherein the specific structure of the appliance adapted thereto is changed based on embodiment 1, and further description is omitted.

Example 8

Referring next to fig. 15 and 16, there is illustrated yet another embodiment of a method of constructing a retention attachment of the present invention, the method comprising the steps of:

step S201, acquiring a dentition model and a shell-shaped appliance model matched with the dentition model;

step S202, selecting a mounting point in an accessory mounting optional area on the dentition model, and constructing a retention accessory based on the mounting point;

here, steps 201 and 202 in this embodiment correspond to steps 101 and 102 in the embodiment shown in fig. 1, respectively, and the specific implementation of each step (including sub-steps) in this embodiment is the same as that in the embodiment shown in fig. 1, which can be understood by referring to the foregoing, and will not be described again.

The difference between the embodiment of fig. 15 and the embodiment of fig. 1 will be described. In particular, in the embodiment of fig. 1, the retention attachment is constructed on the basis of one mounting point P01; in yet another embodiment, shown in fig. 15, the respective corresponding retention attachment is constructed and optimally selected based on two or more mounting points P01.

Specifically, as shown in fig. 15, in still another embodiment, the construction method further includes the following steps.

Step S200, two or more mounting points to be selected are planned in the accessory installation selectable area on the dentition model, all the mounting points are traversed, and the following steps are sequentially executed for each mounting point:

step S202 'selecting a mounting point in the optional accessory mounting area on the dentition model, and constructing a retention accessory based on the mounting point';

and step S203, evaluating the retention force of the constructed retention accessories.

Here, based on this step S200, as will be understood with reference to fig. 16 in conjunction with fig. 2, at least two mounting points P01 are planned within the attachment mounting selectable region a1 on the dentition model 100, and steps S202 and S203 are performed on the basis of each mounting point P01, whereby retention attachments corresponding one-to-one to all the mounting points P01 are constructed, and the retention forces of all the constructed retention attachments are measured for subsequent preference (as described later in step S204).

Preferably, in step 200, the "planning two or more candidate installation points in the optional area for installing attachments on the dentition model", referring to fig. 16, may be implemented as: and planning a plurality of nodes distributed in a row-column matrix in the accessory installation selectable area A1, and taking all or part of the nodes as candidate installation points, thus planning all the candidate installation points.

Further preferably, all of the candidate mounting points include two or more of nine of an inner center point P01MM, a mesial edge center point P01MR, a mesial edge bite end point P01TR, a mesial edge gum end point P01BR, a distal edge center point P01ML, a distal edge bite end point P01TL, a distal edge gum end point P01BL, a bite edge center point P01TM, a gum edge center point P01BM, and the like of the attachment mounting selectable region a 1. For example, if the nine mounting points P01 are all candidate mounting points, through the traversal process in step S200, nine retention attachments corresponding to one another are constructed based on the nine mounting points P01 in steps S202 and S203, and the retention forces of the nine retention attachments are evaluated.

As described above, step S202 is the same as step S102 in the embodiment of fig. 1, and is not repeated, and step S203 is described next.

In step S203, the retention force of the retention accessory is the retention force of the retention accessory to the shell appliance fitted with the retention accessory. In a preferred implementation, step S203 includes the following substeps.

And a substep S2031 of adding the constructed retention accessories to the dentition model as a second dentition model and obtaining a second shell-shaped appliance model matched with the second dentition model.

In this sub-step, the second dentition model is compared with the dentition model obtained in step S201, only in that the second dentition model is additionally added with the retention accessory constructed in step S202, and it can be understood that the position of the retention accessory on the second dentition model is located at the mounting point P01 corresponding to the retention accessory, for example, in step S202, the retention accessory constructed based on the inner center point P01MM in fig. 16 is located at the inner center point P01MM on the second dentition model, particularly, the retention surface of the retention accessory is located at the inner center point P01MM, respectively in step S203; otherwise, the second dentition model is the same as the dentition model in step S201, and the second dentition model will not be described in excess.

In addition, it will also be understood that the second shell appliance model matches the second dentition model, i.e., the second shell appliance model is compared to the shell appliance model obtained in step S201, except that an attachment receiving slot is additionally added to match the retention attachment on the second dentition model.

In the substep S2032, an actuating force for detaching the second shell-shaped appliance model worn on the second dentition model from the second dentition model is obtained, and the actuating force is used as a retaining force of the retaining attachment.

Here, first, the second shell-shaped appliance model is worn on the second dentition model, and then, an actuating force is applied to the second shell-shaped appliance model so that the second shell-shaped appliance model is detached from the second dentition model, the actuating force being a retention force of the retention attachment. The retention effect of the retention attachment on the mating shell appliance can be substantially reflected by the magnitude of the actuation force.

Further, the step of obtaining the actuating force for detaching the second shell appliance model worn on the second dentition model from the second dentition model in the sub-step S2032 is identical to the step of detaching the shell appliance model worn on the dentition model from the dentition model in the sub-step S2021 in terms of the area and direction of the actuating force. For example, as described above, the region of action of the actuating force is selected on the lingual side of the shell-shaped appliance model 200. for example, as described above, the actuating force is directed at a non-zero angle with respect to the long axis of the tooth where the optional attachment mounting region is located, from the gingival end to the occlusal end, and from the lingual side to the labial side, and so on, and as described above, further description will be omitted.

Step S204, determining the final retention accessories and the corresponding mounting points thereof according to the optimal principle of the maximum retention force in all the constructed retention accessories.

As will be appreciated from the foregoing, the greater the retention force of the retention accessory, the better the retention of the retention accessory to the mating shell appliance when mounted at its corresponding mounting point P01. Thus, by traversing all the mounting points P01 and comparing the magnitude of the retention force of the retention accessories constructed based on the mounting points P01, a retention accessory with the optimal retention effect and the mounting point P01 corresponding to the retention accessory can be selected. For example, in step S204, of the 9 retention attachments respectively constructed based on the 9 mounting points P01 in fig. 16, the retention attachment constructed based on the inner center point P01MM is selected to have the largest retention force, so that, in the designed bracket-free invisible appliance for the dentition to which the dentition model is directed, the retention attachment is configured to be constructed based on the inner center point P01MM and is installed on the surface of the dentition corresponding to the inner center point P01MM, and the attachment receiving groove is opened on the shell-shaped appliance at the position corresponding to the inner center point P01 MM.

From the above, the embodiment shown in fig. 15 has the advantages of the embodiment shown in fig. 1, and meanwhile, based on the embodiment shown in fig. 1, by preferentially selecting the retention accessories and the mounting points thereof, the retention effect of the retention accessories on the shell-shaped appliance can be further improved, and the accidental sleeve-removing probability of the shell-shaped appliance can be further reduced.

Further, in accordance with the construction method of the embodiment shown in fig. 15, a construction system of the retention attachment is provided in accordance with still another embodiment of the present invention.

Here, the processor of the present embodiment also includes an acquisition unit, a control unit, and a processing unit, as in the foregoing with respect to the processor of the construction system of fig. 1; also, corresponding to the construction method of the embodiment shown in fig. 15, the processor in this embodiment further includes a traversal unit and a filtering unit.

The acquisition unit is used for acquiring a dentition model and a shell-shaped appliance model matched with the dentition model;

the traversing unit is used for planning two or more mounting points to be selected in the accessory mounting selectable area on the dentition model and traversing all the mounting points;

the control unit is used for controlling the shell-shaped appliance model worn on the dentition model to be taken off from the dentition model;

in the process that the shell-shaped appliance model worn on the dentition model is taken off from the dentition model, the obtaining unit is further used for obtaining the movement track of the reference point, corresponding to the installation point selected by the traversing unit, on the shell-shaped appliance model;

the processing unit is used for establishing a tangent line of one key position point in the motion trail or establishing a straight connection line of two key position points in the motion trail, and the retention accessory is constructed according to each rule;

the acquisition unit is also used for adding the constructed retention accessories on the dentition model to serve as a second dentition model and acquiring a second shell-shaped appliance model matched with the second dentition model; acquiring an actuating force for taking off the second shell-shaped appliance model worn on the second dentition model from the second dentition model, wherein the actuating force is used as a retaining force of a retaining accessory on the second dentition model;

the screening unit is used for determining the final retention accessories and the corresponding mounting points thereof in all constructed retention accessories according to the optimal principle of the maximum retention force.

It should be noted that each unit of the processor can also be used for executing detailed implementation of corresponding steps in the construction method and other steps, and the foregoing description can be specifically referred to.

Further, corresponding to the building method of the embodiment shown in fig. 15, yet another embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, implements the steps in the building method described above.

In addition, the invention also provides a bracket-free invisible orthodontic appliance, the retention accessory of the bracket-free invisible orthodontic appliance is constructed by adopting the construction method shown in fig. 15, and the rest can be referred to the former embodiment, so that the description is not added.

In addition, each of the retention accessories exemplified in the foregoing embodiments 1 to 8 can be constructed, formed and positioned by the construction method and the construction system of the present embodiment.

In summary, compared with the prior art, the invention has the following beneficial effects: the retention force of the retention accessories to the appliance can be improved, and the problem that the appliance is easy to fall off due to insufficient retention force of the retention accessories to the appliance in the prior art is solved; and furthermore, based on the positions of the optional area for installing the accessory, the action area of the actuating force and the like, the condition that the appliance falls off due to the fact that the tongue licks and presses can be avoided, and the retention effect on the appliance is greatly improved.

It should be understood that although the description is made in terms of embodiments, not every embodiment includes only a single embodiment, and such description is for clarity only, and those skilled in the art will recognize that the embodiments described herein may be combined as a whole to form other embodiments as would be understood by those skilled in the art.

The detailed description set forth above is merely a specific description of possible embodiments of the present invention and is not intended to limit the scope of the invention, which is intended to include within the scope of the invention equivalent embodiments or modifications that do not depart from the technical spirit of the present invention.

Claims

1. A method of constructing a retention attachment, wherein the retention attachment includes a bottom surface for attachment to teeth, and a gingival side retention surface, a corner retention surface, and a distal side retention surface connected in this order along a partial edge of the bottom surface, the method comprising the steps of,

2. The method for constructing a fixture attachment according to claim 1, wherein the step of selecting a mounting point in an attachment mounting selectable area on the dentition model, and constructing the fixture attachment based on the mounting point further comprises:

3. The method of claim 2, wherein the corner retention surface is convexly curved in a cross-section perpendicular to the normal of the bottom surface.

4. The method of claim 2, wherein the key location point is selected from a start location point, an end location point defined by an intersection of a boundary of a normal projection space of the attachment mounting selectable region and the motion trajectory, and a transition location point between the start location point and the end location point.

5. The method of claim 4, wherein the first auxiliary line is a tangent line of the starting point, and the second auxiliary line is a straight line connecting the starting point and the ending point.

6. The method of constructing a retention attachment of claim 1, wherein any one of the gingival side retention surface, the angular retention surface, and the distal side retention surface is configured as: and extends away from the bottom surface along a straight line at an included angle of 60-120 degrees with the bottom surface.

7. The method as claimed in claim 6, wherein the gingival side retention surface and the distal side retention surface are respectively configured as a flat surface or a curved surface, and the corner retention surface is configured as a circular cylindrical arc surface.

8. The method of constructing a retention attachment of claim 1, wherein an intersection line of the gingival side retention surface and the bottom surface has a distal-most point distant from the corner retention surface and a proximal-most point intersecting the corner retention surface;

9. The method of constructing a retention attachment of claim 8, wherein the gum-side retention surface is configured to: the plane is formed by two end points of the intersecting line of the bottom surface and the highest point and forms an included angle of 60-120 degrees with the bottom surface;

10. The method of claim 8, wherein on a projection plane normal to said bottom surface, a straight line connecting said distal-most point and said proximal-most point forms an angle of 60 ° to 90 ° with a long axis of a tooth on which said optional attachment mounting region is located;

11. The method of claim 1, wherein an upper edge of any one of the gingival side retention surface, the corner retention surface, and the distal side retention surface defines a maximum height of the retention attachment normal to the floor.

12. The method for constructing a retention attachment according to claim 1, wherein in the step of obtaining the movement trajectory of the reference point corresponding to the mounting point on the shell-shaped appliance model: sequentially recording N coordinates of the reference point in a space coordinate system, and fitting the N coordinates into a curve in sequence, wherein the curve forms the motion track; n is more than or equal to 2, and the N coordinates comprise the initial coordinates of the reference points when the shell-shaped appliance model is worn on the dentition model.

13. The method of constructing a retention attachment as claimed in claim 1, wherein the attachment mounting selectable region is located on a labial surface of the dentition model;

14. The method of claim 13, wherein the step of removing the shell appliance model worn on the dentition model from the dentition model comprises: and taking the midpoint of the gingival edge of the lingual side of the final molar shell unit of the shell-shaped appliance model as the action area of the actuating force.

15. The method of constructing a retention attachment according to claim 1, wherein there are two or more candidate mounting points in the optional area for attachment mounting, and wherein traversing all of the mounting points is performed for each mounting point in turn: the step of selecting a mounting point in the accessory mounting selectable area on the dentition model and constructing the retention accessory based on the mounting point; evaluating the retention force of the constructed retention accessory;

16. The method for constructing a retention accessory as claimed in claim 15, wherein a plurality of nodes are defined in a row-column matrix in the accessory mounting selectable area, and all or part of the nodes are used as candidate mounting points.

17. The method of claim 15, wherein said "two or more alternative mounting points" comprise two or more of an inner center point, a mesial edge bite end point, a mesial edge gum end point, a distal edge center point, a distal edge bite end point, a distal edge gum end point, a bite edge center point, and a gum edge center point of said attachment mounting option.

18. The method of claim 15, wherein the step of evaluating the retention force of the retention attachment comprises:

19. A system for constructing a retention attachment, comprising a memory and a processor, wherein the memory stores a computer program executable on the processor, and the processor executes the computer program to implement the steps of the method for constructing a retention attachment according to any one of claims 1 to 18.

20. A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the steps of the method for constructing a retention attachment according to any one of claims 1 to 18.

21. A bracket-free invisible orthodontic appliance comprising:

a retention attachment constructed using the method of any one of claims 1 to 18, wherein the bottom surface of the retention attachment is configured to attach to teeth on the dentition, and the gingival side retention surface, the corner retention surface, and the distal side retention surface all abut the trough surface of the attachment receiving slot to prevent the appliance from disengaging from the dentition.

22. The bracket-free invisible appliance of claim 21, wherein the appliance comprises a buccal housing and a lingual housing, the accessory receiving slot being provided in the buccal housing and located in any one or more of the housing units of the appliance corresponding to molars and premolars.

23. The bracket-free invisible appliance of claim 22, wherein the accessory receiving slot is located in a shell unit of the appliance corresponding to a last molar and/or a shell unit of the appliance corresponding to a last second tooth.